The set of real numbers symbol is the Latin capital letter “R” presented with a double struck typeface. The symbol is used in math to represent the set of real numbers. Typically, the symbol is used in an expression like this:
In plain language, the expression above means that the variable is a member of the set of real numbers.
The capital Latin letter R is used in mathematics to represent the set of real numbers. Usually, the letter is presented with a "double-struck" typeface when it is used to represent the set of real numbers.
Set of natural numbers.
Set of integers symbol.
The set of rational numbers is denoted with the Latin Capital letter Q presented in a double-struck type face.
The set of complex numbers is represented by the Latin capital letter C. The symbol is often presented with a double-struck font face just as with other number sets. The set of complex numbers extends the real numbers.
The set of real numbers contains the set of rational numbers as well as irrational numbers like pi, e, and the square root of two.